Please explain

Why are the local councils spraying the roads with bitumen then covering with aggregate when the road isn't scalped first nor are the potholes filled in. All this seems to do is make the road look nice whilst camouflaging the existing potholes for you to find with your wheels. Also makes the man hole covers nearly as bad as the potholes, as layer after layer is added making the road noticeable higher than the covers.
What is the point of it when they don't repair the road first?